Long Term Evolution (LTE) is a technical plan developed by the 3rd Generation Partnership Project (3GPP) standardization organization based on the Universal Mobile Telecommunications System (UMTS). The LTE will bring faster and smoother wireless telecommunication networks for mobile users. Currently, the LTE standardization is centralized on the physical layer, the air interface protocol, and the network architecture.
In an LTE system, Physical Downlink Control Channel (PDCCH) is one of the physical layer channels, which is used to transmit the downlink control signaling of the physical layer. The control signaling may include the control messages required for data transmission such as physical resource allocation and modulation mode.
In the LTE system, the physical layer resources are generally scheduled in two ways: dynamic scheduling and persistent scheduling. In the persistent scheduling, resources are reserved by the system, and keep unchanged in the process of sending or receiving data. In the dynamic scheduling, resources are allocated by the system dynamically, and vary with time dynamically in the process of sending or receiving data. Another resource scheduling mode defined in the LTE is semi-persistent scheduling. In the semi-persistent scheduling, the resources are scheduled persistently for initial transmission of the data; and, if the initial transmission is erroneous, Hybrid Automatic Repeat Request (HARQ) retransmission is started, and the resources are scheduled dynamically in the retransmission. After receiving control signaling, sent by the base station, which indicates that the semi-persistent scheduling is activated, a user believes that the corresponding time-frequency resources are reserved for initial transmission by the base station at the time of sending the activation control signaling and the control message indication. The user may send data (uplink) or receive data (downlink) on the reserved resources.
When the user does not need to send or receive data temporarily, that is, the user does not need to use the uplink or downlink reserved resources semi-persistently scheduled, the base station may release the uplink or downlink reserved resources through control signaling. If the channel, on which the uplink or downlink reserved resources in semi-persistent scheduling are configured for the user, is not in good condition or there are other reasons, the base station may reconfigure the uplink or downlink reserved resources through the control signaling.
The activation control signaling has high requirements for receiving performance, especially for the probability of false alarm; therefore, in the prior art, a false alarm of the activation control signaling is checked by using a group of check bits. This group of false alarm check bit(s) belongs to an information field in the format of the activation control signaling. A schematic principle of the false alarm check is as follows: The base station and the user make an appointment that all false alarm check bit(s) are set to 0. Then, Cyclic Redundancy Check (CRC) is passed in the detection of the activation control signaling, but not all of the false alarm check bit(s) are 0, the user determines that the control signaling does not belong to the user itself (that is, a false alarm occurs); and if all of the false alarm check bit(s) are 0, the user determines that the control signaling belongs to the user itself
However, in the prior art, the method for checking a false alarm needs to be improved, so as to further reduce the probability of false alarm, and improve the receiving performance of the control signaling.